Likkutei Sichos Dictionary
The following sites have Yiddish dictionaries:
Faith (Emunah):"Faith" is the spiritual state associated with the inner experience of the highest of the three "heads" of keter, the riesha dlo ityada("unknowable head").
Farbrengen (v. to farbreng):A Chabad Chassidic gathering, for the purpose of inspiring the participants to greater love of Hashem, of their fellow Jew, and of Torah, according to the guidance of Chabad Chassidus
Fear (yirah):"Fear" is the spiritual state associated with the sefirah of gevurah.
Foundation (Yesod):"Foundation" is the ninth of the ten sefirot, and the sixth of the emotive attributes.